This invention relates to a vehicle steering wheel comprising a skeleton and a gas bag module which is axially movably coupled with the skeleton.
Gas bag modules which for actuating the horn are movably mounted on the vehicle steering wheel are referred to as xe2x80x9cfloating hornxe2x80x9d modules. Upon deployment, the gas bag must be firmly attached to the gas bag module in the vicinity of the opening edge, so as not to be torn out of the module by the thrust generated by the gas released. To this end, the gas bag is usually clamped between two metal sheets in the vicinity of the opening edge, a flange in the form of a metal ring being usually placed on the inside of the opening edge. In the prior art, this flange is urged against a flange of the gas generator, so that the gas bag is clamped between these two parts. The gas generator is attached to a gas generator mounting plate which at another point is in turn axially movably mounted on the skeleton or on a part attached to the skeleton. The individual parts should have a stable design so as to introduce the forces, for retaining the gas bag, into the skeleton.
The invention creates a vehicle steering wheel which has less weight, is more stable and is formed of less parts than vehicle steering wheels known so far. This is achieved in a vehicle steering wheel which comprises a skeleton, a gas bag module which is axially movably coupled with the skeleton in such a way that by pressing against the gas bag module a contact is closed for actuating a horn, and a resilient return element for the gas bag module. The gas bag module comprises a gas bag with an opening edge defining an inflation opening as well as comprises a flange clamping the opening edge on an inside of the gas bag for fastening the gas bag. Bearing pins are provided which directly engage the flange and which are attached to one of the skeleton and a part stationarily mounted directly to the skeleton. In the vehicle steering wheel proposed, the force exerted on the flange is preferably directly introduced into the skeleton and not via numerous other connecting elements and parts such as the flange of the generator, a generator mounting plate and a metal sheet on the skeleton. Due to the direct introduction of force into the skeleton or into a part directly mounted on the skeleton less mounting elements are provided than in the prior art, as the load-bearing intermediate metal sheets and their attachments can be omitted.
Preferably, the bearing pins are attached to the skeleton in such a way that an axial movement of the gas bag module together with the bearing pins, for actuating the horn, is permitted. The axial mounting is thus arranged in the vicinity of the steering wheel skeleton, where more room is available than in the vicinity of the gas bag module.
Moreover, on at least one of the bearing pins one of the contacts to be closed may be mounted, so that the bearing pin together with the contact forms a preassembled unit and only few parts will have to be mounted when incorporating the gas bag module in the steering wheel.
The bearing pins can also form a lateral guidance for the gas bag module, so that further guide surfaces become superfluous.
In accordance with a preferred embodiment, the bearing pins are designed as threaded pins. Nuts screwed onto the threaded pins directly engage the skeleton or the part stationarily mounted on the skeleton. On their outer surface, the nuts have a lateral guidance for the gas bag module.
Preferably, the skeleton or the part stationarily mounted directly on the skeleton has a guide sleeve in which slides the nut.
In accordance with another embodiment a latching connection is provided by means of which said bearing pins are fixed to said skeleton. When the bearing pins are designed as threaded pins having a threaded end, a nut with an integrally formed latching nose may, for instance, be screwed onto the bearing pins each at the threaded end.
When each bearing pin is composed of several parts, for instance as threaded pin with a nut screwed onto the same, a gas generator carrier may preferably be clamped between the nut and the flange. Since the gas generator carrier need not absorb any load upon deployment of the gas bag, it may be designed as plastic part, whereby the weight of the vehicle steering wheel will be reduced. In this connection, one embodiment provides that the gas generator carrier is designed as pot-shaped housing of the gas bag module.